Cable with electric connector

Abstract

To provide a cable with an electric connector that can improve transmission characteristics.SOLUTION: A cable with an electric connector comprises a cable and a connector. The cable has a plurality of conductors, and a first dielectric substance that covers the plurality of conductors to expose respective leading ends of the plurality of conductors. The connector has a plurality of second dielectric substances that hold the respective leading ends of the plurality of conductors to expose respective leading end faces of the plurality of conductors to the outside. The plurality of second dielectric substances are formed so that the extension directions of the plurality of second dielectric substances and the plurality of conductors change, while the distance between the plurality of conductors is maintained.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to cables with electrical connectors. [Background technology]

[0002] Patent Document 1 discloses a connector including signal wires, ground wires, and an insulating layer that covers the signal wires and the ground wires so that their respective tip portions are exposed. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2019 / 208091 Summary of the Invention [Problem to be solved by the invention]

[0004] In the connector disclosed in Patent Document 1, a signal line is connected to a mating connector or the like via a signal line contact member, thereby transmitting signals between the connector and the mating connector or the like. In such a connector, since the connection is made via the contact member, stubs (branching of the signal) may occur, which may degrade the transmission characteristics. Therefore, it is desired to improve the transmission characteristics.

[0005] An object of the present disclosure is to provide a cable with an electric connector that is capable of improving transmission characteristics. [Means for solving the problem]

[0006] One aspect of the present disclosure relates to a cable with an electric connector. The cable with an electric connector includes a cable and a connector. The cable has a plurality of conductors and a first dielectric covering the plurality of conductors so as to expose the tip end of each of the plurality of conductors. The connector has a plurality of second dielectrics holding the tip ends of the plurality of conductors respectively so as to expose the tip end surface of each of the plurality of conductors to the outside. In the cable with an electric connector, the plurality of second dielectrics are formed so that the extending direction of the plurality of second dielectrics and the plurality of conductors changes while maintaining the distance between the plurality of conductors. Effect of the Invention

[0007] According to the present disclosure, it is possible to provide a cable with an electric connector that is capable of improving transmission characteristics. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view showing a flat cable with an electric connector according to one embodiment. [Diagram 2] FIG. 2 is a top view showing a flat cable used in the flat cable with electric connector shown in FIG. [Diagram 3] FIG. 3 is a plan view showing the connection surface of the electrical connector shown in FIG. 1 as viewed from the board. [Figure 4] FIG. 4 is a perspective view showing a modified example of the flat cable with electric connector. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] [Description of the embodiments of the present disclosure] First, the contents of the embodiments of the present disclosure will be listed and described. [1] A cable with an electrical connector according to an embodiment of the present disclosure includes a cable and a connector. The cable has a plurality of conductors and a first dielectric covering the plurality of conductors so as to expose the tip end of each of the plurality of conductors. The connector has a plurality of second dielectrics holding the tip ends of the plurality of conductors respectively so as to expose the tip end surface of each of the plurality of conductors to the outside. In this cable with an electrical connector, the plurality of second dielectrics are formed such that the extending direction of the plurality of second dielectrics and the plurality of conductors changes while maintaining the distance between the plurality of conductors.

[0010] In this cable with electrical connector, the connector (second dielectric) holds each of the conductors so that the tip surface of each of the conductors is exposed to the outside. Therefore, when the electrical connector is connected to a mating member (for example, a board on which a connection terminal is formed), each tip surface of the conductors can be directly connected to the terminal of the mating member. This makes it possible to suppress the occurrence of stubs (branching of signals) that occur when parts of the conductors other than their tip surfaces come into electrical contact with the terminal of the mating member. Therefore, this electrical connector can improve the transmission characteristics. Also, in this cable with electrical connector, the extension direction of the second dielectric that holds each conductor is formed so as to change with the extension direction of the conductor. In this case, it is possible to set the attachment angle of the cable to a desired angle with respect to a connection surface including each tip surface of the conductors while matching impedance.

[0011] [2] In the cable with electrical connector of [1] above, the dielectric constant of the dielectric material constituting the second dielectric may be 0.9 or more and 1.1 or less relative to the dielectric constant of the dielectric material constituting the first dielectric. In this case, it becomes easier to match the impedance of the portion of the cable where the conductor is covered by the first dielectric with the impedance of the portion of the cable where the conductor is covered by the second dielectric. This adjusts the impedance of the conductor, thereby further improving the transmission characteristics.

[0012] [3] In the cable with electrical connector of [1] or [2] above, each of the plurality of second dielectrics may be tubular with one of the plurality of conductors disposed inside, and a space may be formed between each of the plurality of second dielectrics. In this case, the dielectric constant of the connector can be reduced compared to when a dielectric exists between adjacent second dielectrics. Therefore, by matching the dielectric constant of the cable with the dielectric constant of the connector, the impedance of the cable with the impedance of the connector can be matched, and electrical signal loss and crosstalk can be suppressed in the cable with connector.

[0013] [4] In the cable with electrical connector of [1] or [2] above, the connector may have a conductor made of a conductive material, the second dielectrics may be provided within the conductor, and the extending directions of the second dielectrics and the conductors may change within the conductor. In this case, the conductor covers the conductor, thereby reducing external noise propagating to each conductor.

[0014] [5] In the cable with electrical connector according to any one of [1] to [4] above, the end faces of the conductors may be located on the same plane as the end face of the second dielectric. In this case, the end faces of the conductors can be easily electrically connected to the mating connector.

[0015] [6] In the cable with electrical connector of any one of [1] to [5] above, the cable may have a first shielding member provided on the first dielectric, and the connector may have a second shielding member provided adjacent to the second dielectric. In this case, it is possible to reduce noise generated from each conductor of the cable or noise propagating to each conductor. As a result, the cable with electrical connector can further improve the transmission characteristics.

[0016] [Details of the embodiment of the present disclosure] Specific examples of the cable with electrical connector according to the present embodiment will be described with reference to the drawings as necessary. Note that the present disclosure is not limited to these examples, but is intended to include all modifications within the scope of the claims and meaning equivalent thereto. In the following description, the same elements in the description of the drawings will be given the same reference numerals, and duplicated descriptions will be omitted.

[0017] FIG. 1 is a perspective view showing a flat cable with an electric connector according to one embodiment. FIG. 2 is a top view of a flat cable used in the flat cable with an electric connector shown in FIG. 1. As shown in FIGS. 1 and 2, the flat cable with an electric connector 1 includes flat cables 10A and 10B and a connector 20. The connector 20 includes a connector body 21, a tip connector 22, and a shielding member 23 (second shielding member). The tip connector 22 is fixed to a front surface 21a of the connector body 21 by adhesive or the like. The shielding member 23 is a frame-shaped member protruding outward from a front surface 22a of the tip connector 22. The shielding member 23 is formed of, for example, a metal. The flat cable 10B has a similar configuration to the flat cable 10A. Therefore, hereinafter, the details of the flat cable 10A will be described, and a description of the flat cable 10B may be omitted.

[0018] The flat cable 10A is, for example, a flexible flat cable (FFC). The flat cable 10A has conductors 11, 14, and 17 as ground conductors, and conductors 12, 13, 15, and 16 (multiple conductors) as signal conductors. The multiple conductors 11 to 17 are arranged in parallel at a predetermined interval from each other, and are insulated from each other by a dielectric 18. The multiple conductors 11 to 17 are made of a conductive metal such as copper, tin-plated soft copper, or nickel-plated soft copper, and have a circular or rectangular cross-sectional shape. The diameter or maximum width of such conductors 11 to 17 may be 350 μm or less, 300 μm or less, or 100 μm or less. The conductors 11, 14, and 17 as ground conductors are adjusted so that their tips are shorter than the conductors 12, 13, 14, and 15 as signal conductors. However, the lengths of the tips of the conductors 11, 14, and 17 and the conductors 12, 13, 14, and 15 may be the same. In this embodiment, for example, a pair of conductors 12, 13 and a pair of conductors 15, 16 are used as differential signal lines. The number of conductors included in the flat cable 10A is not limited to the number (e.g., seven) shown in Figures 1 and 2, and may be two or more. The arrangement order of the signal conductors and ground conductors included in the flat cable 10A is not limited to the arrangement order shown in Figures 1 and 2, and various arrangements can be applied.

[0019] As shown in FIG. 2, each of the conductors 11 to 17 includes a tip portion 11a, 12a, 13a, 14a, 15a, 16a, and 17a. Each of the tip portions 11a to 17a is held by a connector 20, the details of which will be described later. In each of the tip portions 11a to 17a, the dielectric 18 covering is removed, and the conductor portion is exposed. As described above, the tip portions 11a, 14a, and 17a serving as ground conductors are shorter than the tip portions 12a, 13a, 15a, and 16a serving as signal conductors. The tip portions 11a to 17a are provided at their respective tips with tip faces 11b, 12b, 13b, 14b, 15b, 16b, and 17b. The tip faces 11b, 14b, and 17b are areas that are connected to the shielding member 23 when held in the connector 20, and the tip faces 12b, 13b, 15b, and 16b are areas that are directly connected to the mating terminals when the flat cable 1 with electrical connector is connected to a mating member (such as a substrate 50 having a connection terminal provided on its surface).

[0020] The dielectric 18 is a portion that covers and protects the conductors 11 to 17. The conductors 11 to 17 are configured to be insulated from each other by the dielectric 18. The dielectric 18 can be formed, for example, from a dielectric material having a relative dielectric constant of 2.3 or less and a dielectric loss tangent of 0.0014 or less. By covering the conductors 11 to 17 with a dielectric material having such a relative dielectric constant and dielectric loss tangent, the impedance of the conductors 11 to 17 is reduced. The dielectric material constituting the dielectric 18 is, for example, a resin composition mainly composed of polyolefin, polyester, or olefin-based thermoplastic elastomer. However, the dielectric material constituting the dielectric 18 is not limited to these, and various materials can be used as long as they can reduce the impedance of the conductors 11 to 17. The dielectric 18 may be formed by laminating a pair of films made of such a dielectric material to both sides of the conductors 11 to 17, or may be formed by extruding such a dielectric material onto the conductors 11 to 17.

[0021] The flat cable 10A further includes shield layers 19a, 19b (first shield members) disposed on the outside of the dielectric 18. The shield layers 19a, 19b are formed so as to cover substantially the entirety of the dielectric 18. Providing the shield layers 19a, 19b makes it possible to prevent external noise from entering the conductors 11 to 17 and to ensure high-frequency characteristics. Such shield layers 19a, 19b can be formed of, for example, a metal foil such as copper foil or aluminum foil, and can be attached to the outside of the dielectric 18 with an adhesive. Note that, although the ends of the shield layers 19a, 19b are separated from each other in FIG. 1, both ends may be connected by a shield material.

[0022] The connector body 21 of the connector 20 is a cylindrical member having a rectangular parallelepiped outer shape, and is a member that holds the conductors 11 to 17 of the flat cables 10A, 10B. The connector body 21 is provided with insertion holes 21b from the rear to the front, and the flat cables 10A, 10B are inserted into the insertion holes 21b. At this time, the connector body 21 integrally holds the flat cables 10A, 10B by the insertion holes 21b at the rear end side, and at the front end side (the portion close to the tip connector 22), parts of the tip portions of the corresponding conductors 11 to 17 are placed in individual through holes (not shown) that extend forward from the insertion holes 21b. The multiple through holes provided in the connector body 21 are connected to holes in the holding parts 31, 32, 33, 34, 35, 36, and 37 (second dielectric) provided in the tip connector 22, so that the conductors 11 to 17 that pass through the individual through holes provided in the connector body 21 are held by the holding parts 31 to 37. In addition, the tip faces 11b to 17b of the conductors 11 to 17 held by the holding parts 31 to 37 are exposed to the outside of the connector 20 (see FIG. 3). The connector body 21 can be made of resin or metal. When the connector body 21 is made of resin, the connector body 21 may be covered with a metal shell.

[0023] The tip connector 22 is an auxiliary connector that is attached to the front surface 21a of the connector body 21. The tip connector 22 can be made of, for example, metal. In the tip connector 22, the same number of holding parts 31 to 37 as the number of conductors included in the flat cable 10A, and holding parts 41 to 43, 45, and 46 corresponding to the flat cable 10B are formed on the top and bottom. In FIG. 1, the two holding parts for the flat cable 10B corresponding to the holding parts 34 and 37 are hidden, but similar holding parts are provided. These two hidden holding parts and the holding part 41 may be referred to as "holding part 41, etc." hereinafter. The holding parts 31 to 37, the holding part 41, etc., and the holding parts 42, 43, 45, and 46 can be made of the same material as the dielectric 18. In this case, for example, the dielectric constant of the dielectric material constituting the holding portions 31 to 37, the holding portion 41, etc., and the holding portions 42, 43, 45, 46 may be in the range of 0.9 to 1.1 relative to the dielectric constant of the dielectric material constituting the dielectric 18. The holding portions 31 to 37, etc. may be formed from a dielectric material having a lower relative dielectric constant than the dielectric 18. In this case, the side surface of the tip connector 22 may be covered with a metal shell.

[0024] The holding parts 31, 34, 37 and the holding part 41 are holding parts that respectively hold the conductors 11, 14, 17 that are ground conductors. The holding parts 31, 34, 37 and the holding part 41 protrude from the front surface 22a of the tip connector 22. The tip surfaces 11b, 14b, 17b of the conductors 11, 14, 17 and the end surfaces of the holding parts 31, 34, 37 and the holding part 41 are formed in a cylindrical shape on the same plane. This allows the flat cable with electric connector 1 to be electrically connected to a connection point such as a pad of a substrate that is a counterpart member, without the generation of stubs, and suppresses signal reflection caused by stubs. Although it depends on the structure of the connection point of the counterpart (receptacle) to which the conductors 11, 14, 17 are electrically connected, the end faces 11b, 14b, 17b of the conductors 11, 14, 17 do not have to be completely flush with the end faces of the holding parts 31, 34, 37 and the holding part 41, etc., and a deviation of several μm is permitted. The conductors 11, 14, 17 may protrude slightly from the end faces as long as the connection points on the receptacle side are slightly recessed, or vice versa, as long as the two are configured to be electrically connected. The holding parts 31, 34, 37 and the conductors 11, 14, 17, which are ground conductors, may have the same shape as the signal conductors described later.

[0025] The holding portions 31, 34, 37, and 41 are provided with slits in parts thereof. The shielding member 23 is passed through the slits and comes into contact with the tips 11a, 14a, and 17a of the conductors 11, 14, and 17, thereby conducting the shielding member 23 and the conductors 11, 14, and 17. As a result, the conductors 11, 14, and 17, which are ground conductors, have the same potential as the shielding member 23 and are grounded. The shielding member 23 is provided adjacent to the holding portions 32, 33, 35, and 36 and the holding portions 42, 43, 45, and 46, which will be described next, so as to house them inside.

[0026] The holding parts 32, 33, 35, 36 and the holding parts 42, 43, 45, 46 are cylindrical holding parts that hold the signal conductors 12, 13, 15, 16, respectively. The holding parts 32, 33, 35, 36 and the holding parts 42, 43, 45, 46 are formed so that the extending direction is bent (changed) from the horizontal direction to the vertical direction, for example, by 90 degrees, while keeping the distance (pitch) between the conductors constant, while containing the corresponding conductors 12, 13, 15, 16. The angle at which the holding parts 32, 33, 35, 36 and the holding parts 42, 43, 45, 46 are bent (for example, the angle at the point S in FIG. 1) is not limited to 90 degrees, and may be, for example, between 90 degrees and 150 degrees, between 90 degrees and 120 degrees, or may be an obtuse angle. Such curved holding parts 32, 33, 35, 36 and holding parts 42, 43, 45, 46 can be obtained, for example, by inserting a conductor into a linearly extending cylindrical dielectric, and then bending the dielectric together with the conductor contained therein at a predetermined angle. In order to keep the pitch between the conductors constant, the dielectric may be bent using a plate member that fixes the tip of each dielectric. After bending the dielectric, the conductor may be passed through the dielectric.

[0027] Furthermore, the holding parts 32, 33, 35, 36 and the holding parts 42, 43, 45, 46 are formed so that the tip faces 12b, 13b, 15b, 16b of the conductors 12, 13, 15, 16 and the end faces 32a, 33a, 35a, 36a of the holding parts 32, 33, 35, 36 and the end faces 42a, 43a, 45a, 46a of the holding parts 42, 43, 45, 46 are on the same plane at the bent ends (see FIG. 3). This allows the flat cable with electric connector 1 to be electrically connected to a connection point such as a pad of the substrate 50, which is the counterpart member, without the generation of stubs, and suppresses signal reflection caused by stubs. Although it depends on the structure of the connection point of the counterpart (receptacle) to which conductors 12, 13, 15, 16 are electrically connected, end faces 12b, 13b, 15b, 16b of conductors 12, 13, 15, 16 do not have to be completely flush with the end faces of holding parts 32, 33, 35, 36 and holding parts 42, 43, 45, 46, and a deviation of several μm is permitted. Even if conductors 12, 13, 15, 16 protrude slightly from the end faces, it is sufficient as long as the connection points on the receptacle side are slightly recessed, or vice versa, as long as the two are configured to be electrically connected.

[0028] When a flat cable 1 with an electrical connector having such a configuration is connected to a substrate 50, since the holding portions 32, 33, 35, 36 and the holding portions 42, 43, 45, 46 which hold the conductors 12, 13, 15, 16, which are signal conductors, respectively, are bent, the flat cables 10A, 10B can be wired in a direction along the main surface 51 of the substrate 50 with the end faces 12b, 13b, 15b, 16b of the conductors 12, 13, 15, 16 connected to the main surface 51 of the substrate 50.

[0029] In the flat cable with electric connector 1, the dielectric constant of the dielectric material constituting the holding parts 32, 33, 35, 36 and the holding parts 42, 43, 45, 46 may be 0.9 or more and 1.1 or less relative to the dielectric constant of the dielectric material constituting the dielectric 18 of the flat cables 10A, 10B. In this case, the impedance of the portions where the pair of conductors 12, 13 and the pair of conductors 15, 16 are covered by the holding parts 32, 33, 35, 36 and the holding parts 42, 43, 45, 46 matches the impedance of the portions where the pair of conductors 12, 13 and the pair of conductors 15, 16 are covered by the dielectric 18 of the flat cables 10A, 10B. This makes it possible to suppress loss and crosstalk of the electric signals propagating through the signal conductors.

[0030] In the flat cable with electric connector 1, each of the holding parts 32, 33, 35, 36 and the holding parts 42, 43, 45, 46 has a cylindrical shape with the conductors 12, 13, 15, 16 arranged inside, and a space is formed between the holding parts 32, 33, 35, 36 and the holding parts 42, 43, 45, 46. This allows the dielectric constant of the connector to be reduced compared to when a dielectric exists between the adjacent holding parts 32, 33, 35, 36 and between the adjacent holding parts 42, 43, 45, 46. This allows the dielectric constant of the part of the flat cable 10A, 10B where the dielectric 18 is present to be matched with the part of the flat cable 10A, 10B covered by the holding parts on the tip side, thereby allowing impedance matching over the entire length of the flat cable with connector. This allows the loss and crosstalk of the electric signal propagating through the signal conductor to be suppressed.

[0031] In the flat cable with electric connector 1, the flat cables 10A, 10B have shield layers 19a, 19b provided on the dielectric 18, and the shield layers 19a, 19b are electrically connected to a shield member 23 and a ground conductor via a metal connector 20 or a metal shell. The shield member 23 and the ground conductor are connected to a ground circuit of the connection partner. This makes it possible to reduce noise generated from or propagated to each conductor of the flat cables 10A, 10B.

[0032] Although the embodiments of the present disclosure have been described above in detail, the present disclosure is not limited to the above-described embodiments and can be applied to various embodiments. For example, in the above-described embodiments, the two flat cables 10A, 10B are held by the connector 20, but the number of flat cables 10A, 10B included in the flat cable with electric connector 1 is not particularly limited, and may be one flat cable or three or more flat cables.

[0033] As shown in Fig. 4, the flat cable with electric connector 1A according to the modified example may include a connector 20A having a shield member 23A. The shield member 23A is configured to include an upper shield member 25, a middle shield member 26, and a lower shield member 27. Each of the shield members 25 to 27 is formed of an L-shaped metal plate and extends to cover the holding parts 32, 33, 35, 36 and the holding parts 42, 43, 45, 46 (see Fig. 1) up to their tip surfaces. In this modified example, the conductors 11, 14, 17 (conductors held by the holding parts 31A, 41A) which are ground conductors extend and are bent in the same shape as the conductors 12, 13, 15, 16 which are signal conductors, and are formed so that the tip surfaces of the ground conductors are located on the same plane (the main surface 51 of the substrate 50) as the tip surfaces of the signal conductors. In the flat cable with electrical connector 1A of this modified example, the protruding portion of the signal conductor (the bent portion covered by the holding portion) is surrounded by shielding members 25 to 27, so that the impedance of that portion becomes a predetermined value and the impedance can be matched with the flat cable main body (the portion covered by the dielectric). [Explanation of symbols]

[0034] 1,1A...Flat cable with electrical connector 10A, 10B...Flat cable 11, 14, 17…Conductor 12, 13, 15, 16...Conductor 11a, 12a, 13a, 14a, 15a, 16a, 17a...Tip 11b,12b,13b,14b,15b,16b,17b...Tip surface 18...Dielectric (first dielectric) 19a, 19b...Shield layer (first shield member) 20,20A…Connector 21…Connector body 21a...Front 21b…insertion hole 22…Tip connector 22a...Front 23, 23A...Shielding member (second shielding member) 25, 26, 27…Shielding material 31,31A,34,37,41,41A...Holding part 32, 33, 35, 36, 42, 43, 45, 46...holding portion (second dielectric) 32a,33a,35a,36a,36a,42a,43a,45a,46a...end surface 50…Substrate 51...Main surface

Claims

1. a cable having a plurality of conductors and a first dielectric covering the plurality of conductors so as to expose a tip portion of each of the plurality of conductors; a connector having a plurality of second dielectrics holding the respective tip portions of the plurality of conductors so that the tip surfaces of the respective conductors are exposed to the outside, The plurality of second dielectrics are formed such that the extending directions of the plurality of second dielectrics and the plurality of conductors change while maintaining a distance between the plurality of conductors. Cable with electrical connector.

2. The relative dielectric constant of the dielectric material constituting the second dielectric is a value of 0.9 or more and 1.1 or less relative to the relative dielectric constant of the dielectric material constituting the first dielectric.

2. The cable with electrical connector according to claim 1.

3. Each of the plurality of second dielectrics has a cylindrical shape in which one of the plurality of conductors is disposed inside, and a space is formed between each of the plurality of second dielectrics.

3. The cable with electrical connector according to claim 1 or 2.

4. The connector has a conductor formed from a conductive material; The plurality of second dielectrics are provided within the conductor, and the extending direction of the plurality of second dielectrics and the plurality of conductors changes within the conductor.

3. The cable with electrical connector according to claim 1 or 2.

5. The tip surfaces of the plurality of conductors are located on the same plane as the end surface of the second dielectric.

3. The cable with electrical connector according to claim 1 or 2.

6. the cable has a first shield member disposed on the first dielectric; The connector has a second shield member disposed adjacent to the second dielectric.

3. The cable with electrical connector according to claim 1 or 2.

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